This invention relates to the steering system of a vessel. Particularly, it is an amplifier, composed of solid state electronic devices on a printed circuit board, which is incorporated into the vessel's steering system and provides the means whereby the directional commands from the helm unit are transmitted to the rudder.
Various earlier patents have disclosed inventions relating to the steering systems of vessels. In Spurgin, U.S. Pat. No. 4,342,274; Cavil, U.S. Pat. No. 3,739,738; and, Wesner, U.S. Pat. No. 4,055,135 means of detecting steering errors and failures were disclosed. However, the inventions disclosed by these patents did not provide for correcting the error; they only providing for signalling that an error or failure had occurred. Whereas, the present invention compares the helm position to the rudder position and causes rudder movement, if necessary, based on the result of the comparison.
A remote control apparatus for marine engines which provided an auxiliary controller located in one area of the vessel, a main controller located in the main control room and a means whereby engine control is switched from the auxiliary controller to the main controller or from the main controller to the auxiliary controller was disclosed in Inoue, U.S. Pat. No. 4,099,476.
Hirokawa, U.S. Pat. No. 3,696,282 disclosed an auto pilot system in which the set course signal and the heading signal are supplied to a comparator which feeds a servo motor through an operational device to control the ship.
But, while these inventions provide a means for transferring engine control and a means for maintaining a preset course, they do not provide primary steering means as does the present invention.
Control systems are disclosed in DeVries, U.S. Pat. No. 4,301,759 and in Tatum, U.S. Pat. No. 3,390,614. The DeVries inventions uses a plurality of control members coupled with one another and with the device to be controlled. The Tatum invention involves wave-shaping circuitry for the command and response signals. Whereas, the present invention is an amplifier which takes its input from the helm and feedback potentiometers, compares the inputs, determines the proper direction for the rudder to move and outputs to the appropriate relay to energize solenoids and cause rudder movement. In addition, the present invention provides fault detection circuitry which energizes a relay whena fault is detected and light emitting diodes which illuminate to indicate which output the amplifier is energizing.